DIC8

1. contains two independent or identical 2 to 4 decoders

(a) 74X130

(b) 74X119

(c) 74X139

(d) 74X129

 

2. A seven segment decoder has as its input code

(a) 3 bit hex

(b) 6 bit excess 3

(c) 4 bit BCD

(d) 3 bit octal

 

3. is a priority encoder

(a) 74 × 48

(b) 74 × 144

(c) 74 × 146

(d) 74 × 148

 

4. EO L signal is an enable output designed to be connected to input of another 74 ×148.

(a) EO L

(b) EO H

(c) EI L

(d) EI H

 

5. contains four independent Non - inverting three state buffer.

(a) 74 × 129

(b) 74 × 120

(c) 74 × 126

(d) 74 × 136

 

6. For 74 × 151, input 0001 produces

(a) D1&D21

(b) D5&D51

(c) D1&D11

(d) D5&D61

 

7. ABCD are four naturally BCD digits, the Boolean expression for combinational logic circuit which detect numbers

that are greater than or equal to 7 is

(a) [A + BCD]1

(b) A + BCD

(c) A + B+CD

(d) A + BC+D

 

8. has cascading inputs for combining multiple ’85s to create comparator for more than four bits.

(a) 74 × 138

(b) 74 × 153

(c) 74 × 280

(d) 74 × 85

 

9. Parity checking function F0 for odd parity is

(a) D2 _ D1 _ D0

(b) D2 _ D1 _ P0

(c) [D2 _ D1 _ D0 _ P0]1

(d) D2 _ D1 _ D0 _ P0

 

10. For carry look ahead adder (xi, yi,Ci inputs), then Ci+1 is

(a) xiyi + (xi − yi)Ci

(b) xiyi + (xi + yi)Ci

(c) xiyi + (xi + yi) + Ci

(d) xiyi(xi + yi)Ci

 

11. For 74 x 382, if S2 S1 S0 =110, then F is

(a) A1B1

(b) A1 _ B

(c) A _ B

(d) A · B

 

12. One of the following VHDL statement is used for left rotate in 6 function barrel shifter

(a) when Lrotate ) Dout < = Vrol(DIN, S);

(b) when Lrotate ) Dout <= VSrl(DIN, S);

(c) when Lrotate ) Dout <= Vror(DIN, S);

(d) when Lrotate ) Dout <= VSll(DIN, S);

 

13. 74LS109 has the following characteristic equation.

(a) Q_ = S + R1.Q

(b) Q_ = EN.D + EN1.Q

(c) Q_ = D

(d) Q_ = J.Q1 + K L.Q

 

14. Set up time margin is

(a) tclk + tffpd(max) − tcomb(max) + tsetup

(b) tclk − tffpd(max) − tcomb(max)tsetup

(c) tclk − tffpd(max) − tcomb(max)

(d) tclk − tffpd(max) − tcomb(max) − tsetup

15. In 74 ×175, are buffered.

(a) clock, D

(b) CLR, Q

(c) clock and CLR L

(d) 1Q

 

16. GAL22V10 has tCF =

(a) 10 or 1.5

(b) 13 or 2.5

(c) 5 or 20

(d) 12 or 3.5

 

17. In Johnson counter using 74 × 194 , LIN serial input connected to

(a) QA1

(b) CLR L

(c) TE

(d) QA

 

18. MTBF (tr) is

(a) [exp(tr/_)]/[T0.f.a]

(b) [log(tr/_)]/[T1.f.a]

(c) [erfc(tr/_)]/[T0.f.a2]

(d) [exp(tr)][T0.f ]

 

19. is used to reduce the decoder size in ROM

(a) Two dimensional decoding

(b) five dimensional decoding

(c) four dimensional decoding

(d) one dimensional decoding

 

20. supports burst mode.

(a) Extended data out DRAM

(b) SRAMs output buffer

(c) ZBT SSRAM with pipelined outputs

(d) late write SSRAM with flow through outputs